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A265395 Record values in A265388. 4
0, 6, 15, 33, 91, 435, 703, 1891, 2701, 12403, 18721, 38503, 49141, 79003, 88831, 104653, 146611, 188191, 218791, 226801, 269011, 286903, 385003, 497503, 597871, 665281, 721801, 736291, 765703, 873181, 954271, 1056331, 1314631, 1373653, 1537381, 1755001, 1869211, 1987021, 2035153, 2284453, 2741311, 3059101, 3270403, 3363121, 3913003 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Question: Are all terms apart from 0 and 435 (= 3*5*29) semiprimes? See also comments in A265394 & A265396.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..192

FORMULA

a(n) = A265388(A265394(n)).

PROG

(PARI) lista(nn) = {r = 0; for (n=1, nn, nr = gcd(vector(n-1, k, binomial(2*n, 2*k))); if (nr > r, print1(nr, ", "); r = nr); ); } \\ Michel Marcus, Dec 08 2015. Note: this gives correct value for a(1) only from PARI version 2.8 onward, see A265388 for why. - Antti Karttunen, Dec 11 2015

CROSSREFS

Cf. A265388, A265394, A265396.

Sequence in context: A213779 A051410 A083052 * A232604 A120849 A030661

Adjacent sequences:  A265392 A265393 A265394 * A265396 A265397 A265398

KEYWORD

nonn

AUTHOR

Antti Karttunen, Dec 08 2015

STATUS

approved

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Last modified May 26 22:57 EDT 2019. Contains 323597 sequences. (Running on oeis4.)